Welcome to CDC stacks | A feasibility study for the detection of weak electromagnetic signal/bursts with hard-limited arrays - 9051 | National Institute for Occupational Safety and Health

Note: Javascript is disabled or is not supported by your browser. For this reason, some items on this page will be unavailable. For more information about this message, please visit this page:
About CDC.gov

"The objective of this report was to investigate the use of a noncoherent detector based on polarity-coincidence statistic. Two channel, polarity-coincidence and polarity-difference, statistics were analyzed. The signal, common to both channels, consists of sinusoidal bursts where the exact frequency of the signal is nearly known, but other parameters such as amplitude, phase, and pulse starting time are unknown. The noise inputs are dependent, narrow band, Markov processes. It is shown that the performance depends not only on the signal uncertainties, but on the precise shape of the cross-correlation functions between the noise inputs. By using two polarity-difference statistics in addition to the polarity-coincidence statistic, it is shown that the decrease in performance, as well as the cost of hard limiting due to correlated inputs, can be made small." - NIOSHTIC-2

The Bureau of Mines has conducted field studies in coal mines throughout the United States to determine the effectiveness of electromagnetic techniques in locating miners trapped underground following a mine accident. Data from these tests have been ...

Proceedings of Thru-the-Earth Electromagnetics, August 15-17,1973, Colorado School of Mines, p. 62-72

Series:

Proceedings of Thru-the-Earth Electromagnetics, August 15-17,1973, Colorado School of Mines

Description:

The use of radio signals for underground communications was considered as early as the mid-1920's [1] - [4] . However, early experiments did not produce promising results with the type of equipment that was available then [5] . With advancements in s...

Papers presented at a U.S. Bureau of Mines (USBM) technology transfer seminar describe the causes of violent material failure in U.S. mines, measurement techniques for monitoring events that result in violent failure, and mitigation techniques for co...

"In its role of providing technical assistance to the mining industry, the Bureau of Mines' Tuscaloosa Research Center has conducted research to develop trapped miner location systems which would aid in locating miners trapped by underground mining d...

Abstract-Underground mines are typically extensive labyrinths that employ many people working over an area of many square miles; exten¬sive analysis of mine-communications systems has identified specific problem areas, in particular the excessive ti...